To politics and the anatomy of a smear. For weeks the powerful chairman of the senate foreign relations committee robert menendez has been denying reports he paid women for sex in the douminican republic and one woman said she was paid to lie about the senator. Brian ross is here with all the details on the story that wasn't. Good morning, brian. Good morning, george. That's true. American politics as you know knows few lips and both parties have played their share of dirty strings. In the case of menendez he appears to be the victim of a very dirty trick involving sex, lies and videotape. Here's how it happened. As menendez campaigned for re-election last year, republican operatives secretly went into overdrive to implicate him in a sex scandal. Is that the same person you had sex with? Reporter: They helped arrange interviews with this woman and this one and this one who all told abc news the senator paid them for sex. Reporter: It supposedly happened at casa de campo and one of the homes of the campaign donors where they claimed in reports that surveillance teams learned of raucous parties, everyone naked, of course, but none of the women could produce identity cards with their real names. And they all provided the same story almost word for word as if they had been coached. At least according to a sworn affidavit filed in court this week by one of the three women who says it was all a lie, not the truth, that she and the others were paid to use fake names and make up a story about sex with the senator. I think it's a pretty elaborate plot to take down a sitting senator. Reporter: Abc news did not report the allegations last year but two of the women also talked to a conservative news website "the daily caller" which ran the story and continues to stand by it. Senator menendez said tuesday it was all an outrage. These are false smears that began during my election in an attempt to affect the election for the senate. While the allegations about the prostitutes may have been discredited the senator still faces an ethics inquiry into his relationship with that donor who provided him with private plane flights and for whom menendez intervened allegedly to obtain contracts, much less sexy but potentially much more significant. Okay, brian, thanks very much.

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